Question

Catalog Age lists the top 17 U.S. firms in annual catalog sales. Dell Computer is number one followed by IBM and W.W. Grainger. Of the 17 firms on the list, 8 are in some type of computer-related business. Suppose four firms are randomly selected.a. What is the probability that none of the firms is in some type of computer-related business?b. What is the probability that all four firms are in some type of computer-related business?c. What is the probability that exactly two are in non-computer-related business?